Battery

ABSTRACT

A device for a battery with a spacer preventing direct physical contact between first and second batteries arranged in physical series. A resilient conductor providing an electroconductive contact between a center electrode of the first battery and a terminal electrode of the second battery is held by the spacer.

This application is a division of application Ser. No. 08/196,860, filedFeb. 15, 1994.

BACKGROUND OF THE INVENTION

The field of the present invention is devices for protecting batteryelectrodes.

Dry cell batteries typically used for portable devices such asflashlights, toys and the like are cylindrical and are provided with acenter electrode and a terminal electrode. The center electrode isusually formed as a pin like protrusion having a diameter which is muchsmaller than the outside diameter of the battery. This center electrodeusually forms the positive pole. At the other end of the battery, aterminal electrode is formed which is shaped as a flat contact platehaving a much larger diameter than the center electrode. Frequently, thebatteries are arranged physically as well as electrically in series inthat the center electrode of a first battery directly contacts theterminal electrode of a second battery. If more than two batteries areprovided, the center electrode of the second battery directly contacts aterminal electrode of a third battery and so on.

In a flashlight for example, an electrical circuit is typicallyestablished from one electrode of a battery, e.g. the center electrodeof the foremost battery, through a conductor to a switch, and then toone electrode of the lamp bulb. After passing through the filament of alamp bulb, the electric circuit emerges through a second electrode ofthe lamp bulb in electroconductive contact with a conductor, which inturn is etectroconductively connected with the flashlight housing. Theflashlight housing itself when made of metal, or a conductor extendingalong the inner side of the housing, e.g. if the housing is made ofplastic, typically provides an electroconductive path to an electricalconductor, generally a spring element, which is in contact with theother electrode of a battery, i.e. typically the terminal electrode ofthe rearmost battery. Actuation of the switch to complete the electricalcircuit enables electrical current to pass through the filament, therebygenerating light which is typically focussed by a reflector to form abeam of light.

In the case of medium and larger sized batteries or rechargeable storagebatteries, which are often used in flashlights for public safetypurposes by police and fire protection personnel, the electrodes of thebatteries may be deformed by physical impact to which the flashlight maybe subjected. On the one hand, the terminal electrode might be deformedsince it comprises a relatively large diameter and, therefore, a lowrigidity. On the other hand, the center electrode might be deformedsince it is subjected to a relatively high compressive stress due toit's small diameter. In particular, it often happens that besides adeformation of the pin like protrusion itself another deformationpushing the whole pin like protrusion along the center axis of thebattery takes place. Although the problems above can occur if only twobatteries are connected in series, the electrodes are even more likelyto be deformed if a column consisting of a larger number of batteries isprovided, e.g. a column of four or five batteries, since the weight ofthe battery column is larger when more batteries are provided.Therefore, the impact shock received by the electrodes is increased withgreater numbers of batteries. The probability of a deformation is stillhigher if heavier batteries comprising a larger outside diameter areused since in this case the impact shock is still further increased. Ifan extensive deformation of the electrodes has taken place, the rearmostelectrode might loose contact with the rearmost conductor which isgenerally a spring conductor, or the foremost electrode might loosecontact with the conductor connected to one of the two electrodes of thelamp bulb. Moreover, it is possible that the electrodes of the batterieswill loose contact with each other so that they are spaced with respectto each other in lengthwise direction. In this case, the electriccircuit is no longer closeable and therefore the lamp bulb can no longerbe switched on.

SUMMARY OF THE INVENTION

The present invention is directed to a device for protecting batteryelectrodes. The device includes a spacer to displace the end of abattery from a terminal and a resilient conductor to extend effectivelythe electrode to overcome the displacement.

In a first and separate aspect of the present invention, a deviceincluding a resilient conductor and a spacer are arranged such that thespacer is annularly disposed and the resilient conductor extendsoutwardly of the spacer in a first direction such that electricalcontact may be achieved with both an electrode of the associated batteryand a terminal from which the battery has been displaced by the spacer.

In a second and separate aspect of the present invention, theaforementioned device may include a nonconductive ring as a spacer of adiameter to match the battery casing diameter of a selected standardbattery. The spacer may be of sufficient thickness to exceed theextension of a center electrode protruding from the end of a battery.These relationships assist in locating the device and avoiding impactstresses on the electrodes of a standard dry cell battery.

In a third and separate aspect of the present invention, a device havinga resilient conductor and a spacer is contemplated. The conductor isdefined by a central conductive element, resilient in constructionlocated at the terminal of a battery. The spacer is defined by anextension on the case which extends to or beyond the height of thebattery terminal. The resilient conductor extends outwardly of thatextension on the case.

In a fourth and separate aspect of the present invention, a deviceincorporating one or more of the foregoing aspects is placed inassociation with a flashlight where dry cell batteries areconventionally arranged in physical series. Without the device, thisarrangement can result in damage to the battery electrodes upon axialimpact of the flashlight. The device provides for protection of theelectrodes.

Accordingly, it is an object of the present invention to provide adevice for protecting conventional dry cell batteries. Other and furtherobjects and advantages will appear hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a section of a first embodiment of the battery devicedisposed between adjacent batteries.

FIG. 2 shows a front view of the first embodiment of the battery device.

FIG. 3 shows a section of a first embodiment of the battery device.

FIG. 4 shows a section of a second embodiment of the battery devicedisposed between adjacent batteries.

FIG. 5 shows a front view of the second embodiment of the batterydevice.

FIG. 6 shows a section of a second embodiment of the battery device.

FIG. 7 shows a section of a flashlight provided with said batterydevice.

FIG. 8 shows a section of a flashlight similar to FIG. 7 butadditionally provided with a foremost battery device.

FIG. 9 shows a section of a another embodiment showing a batteriesaccording to the invention with a resilient conductor portions disposedtherebetween.

FIG. 10 shows a side view of the battery device according to the thirdembodiment.

FIG. 11 shows a front view of the battery device shown in FIG. 10.

FIG. 12 shows a rear view of the battery shown in FIG. 10.

FIG. 13 shows a section of a fourth embodiment showing another kind ofbattery device according to the invention with resilient conductorportions disposed therebetween.

FIG. 14 shows a side view of the battery device according to the fourthembodiment.

FIG. 15 shows a front view of the battery device shown in FIG. 13.

FIG. 16 shows a rear view of the battery shown in FIG. 13.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

As shown in FIG. 1, a plurality of batteries 1 are connected in seriesin a manner such that they form a column. This column might be providedwithin a housing or barrel 2 of the electric apparatus. Every battery 1is provided with a center electrode 3 which is typically the positivepole; and with a terminal electrode 4 which is typically the negativepole of the battery 1. A device, generally designated 5, is sandwichedbetween adjacent batteries 1. The device 5 is also shown separately inFIGS. 2 and 3.

The device 5 is provided with a spacer 6 and a resilient conductor 7.The spacer 6 has two opposing recesses 8 receiving the resilientconductor 7. The spacer 6 is annularly disposed. As shown, itconstitutes a ring which may fit within a flashlight barrel 2 or thelike. The ring 6 is sized to abut against an end 9 of a battery casing10 for a given standard size battery and is thicker than the distancethe center electrode 3 on the given size of standard dry cell batteryextends beyond the end of the battery casing. As such flashlight barrels2 are sized to accommodate specific standard sized cells 1, the ring 6will also be appropriately located within the barrel 2 to abut againstthe ends 9 of the battery casings 10.

The resilient conductor 7 is integrally formed from a strip of metalsheet by bending. Two leaf springs are formed to be substantiallycongruent with respect to each other but slightly bent apart from eachother at their middle portion as shown in FIG. 3. A loop connects thetwo defined leaf springs.

The electroconductive contact between the electrodes 3 and 4 of theadjacent batteries 1 is provided by the resilient conductor 7. Theconductor 7 is elastically deformed by the adjacent batteries 1 in amanner such that the resilient conductor 7 is pressed against theelectrodes 3 and 4 to insure adequate contact.

FIGS. 4 to 6 show a second embodiment of the battery device, generallydesignated 11. As shown in the drawings the resilient conductor 12 isformed as a helical spring which is built by pressing and cutting around plate in a spiral-like manner and deforming it to extend thespiral axially. Moreover, the round plate is punched to provide anannular rim 13. The spacer 14 according to the second embodiment isprovided with an annular groove 15 into which the annular rim 13 isinserted.

As shown in FIG. 4, the spacer portion 14 is sandwiched between the ends9 of the battery casings as already demonstrated by the firstembodiment. The center electrode 3 is pressed against the resilientconductor 12 formed as a spiral spring, i.e., against that innermostturn of the spring which has the smallest diameter. On the other hand,the terminal electrode 4 is pressed against one or more of the outerwindings of the spring.

FIG. 7 shows a section of a flashlight comprising the batteries 1 andthe battery device 5 according to the first embodiment sandwichedbetween the batteries 1. The batteries 1 and the battery device 5 aredisposed within a flashlight housing 16 which comprises a cylindricalbarrel 17, a tailcap 18 and a head assembly 19. For the sake ofsimplifying the drawings, only two batteries 1 are shown. Depending onhow long the flashlight is, more batteries 1 with respective devices 5may be provided, e.g., five batteries 1 with four battery devices 5sandwiched therebetween.

The tailcap 18 is provided with a spring-like electrical conductor 20which is in contact with the terminal electrode 4 of the rearmostbattery 1. On the other hand, the center electrode 3 of the foremostbattery 1 is contacted by another spring-like conductor 21. Thisconductor 21 is connected by means of a switch 22 schematically shown inthe drawings to a first electrode 23 of a lamp bulb 24. The firstelectrode 23 is connected with a filament 25 of the lamp bulb 24. Thisfilament 24 in turn is electroconductively connected with a socket 26 ofthe lamp bulb 24. The socket 26 is electroconductively connected withthe flashlight housing 16 made of aluminum. In the case that the switch22 is closed which might be done by pressing a button 27, electricalcurrent can flow through the batteries 1 and the battery device 5therebetween to the center electrode 3 of the foremost battery 1 andfurther through the spring-like conductor 21 and the switch 22 throughthe electrode 23, the filament 25, the socket 26, the flashlight housing16, a screw thread 28, the tailcap 18 and the spring-like rear conductor20 to the terminal electrode 4 of the rearmost battery 1. With theswitch 22 closed, the lamp bulb emits light. Since the batteries 1 arein contact with each other by means of the battery devices 5 and notdirectly by means of the battery electrodes 3 and 4, the batteries 1 arenot deformed and therefore permanent electroconductive contact isprovided between the electrodes 3 and 4 of the batteries 1.

FIG. 8 shows a section of the flashlight having a similar constructionsas the one shown in FIG. 7. The same and analogous elements aredesignated by the same reference numbers and the description thereof isomitted to avoid repetitions. The main difference between the embodimentshown in FIG. 7 and 8 is that, instead of the spring-like conductor 21contacting the center electrode 3 of the foremost battery, asubstantially non resilient conductor 36 is provided which iselectro-conductively contacted by a foremost battery device 5. Thisguarantees that no deformation of the center electrode 3 can take placeand a good electroconductive contact is always maintained between thenon resilient conductor 36 and the center electrode 3 of the foremostbattery 1 in the same way as if positioned between two adjacentbatteries.

FIG. 9 shows another embodiment employing batteries 32 designed in amanner such that a center electrode 29 and a terminal electrode 30 areprotected against deformation. A resilient conductor 31 provideselectroconductive contact between the adjacent batteries 32 while theelectrodes 29 and 30 are spaced from each other. A cup-shaped receivingspace 33 for accommodating the resilient conductor 31 is bordered by aspacer 34 which is formed as an annular rim 34 encircling the centerelectrode 29. The cup-shaped receiving space 33 is closed by theterminal electrode 30 of the adjacent battery 32. According to theembodiment shown, the resilient conductor 31 is fixed to the centerelectrode 29. However, the resilient conductor 31 may also be looselyfitted into the receiving space 33 and resiliently pressed against theadjacent electrodes 29 and 30.

FIG. 10, 11 and 12 show the battery 32 separately. As shown in FIG. 10,the resilient conductor 31 of this embodiment does not protrude beyondthe annular rim 34 since the terminal electrode 30 protrudes into thecup-shaped receiving space 33. However, it is also possible that theterminal electrode 30 is plain or even recessed and the resilientconductor 31 protrudes beyond the annular rim 34 to contact the terminalelectrode 30 of the adjacent battery 32. It is also possible that boththe center electrode 29 and the terminal electrode 30 are shapedidentically and both provided with an resilient conductor 31.

As becomes apparent from FIGS. 10 and 11, the resilient conductor 31 issomewhat similar to the resilient conductor 7 shown in the firstembodiment. A similar embodiment of the battery 32 is shown in FIG. 13to 16. The same and analogous elements are designated by the samereference numbers and the description thereof is omitted to avoidrepetitions. The main difference between the embodiment shown in FIG. 9to 12 and the embodiment shown in FIG. 13 to 16 is the different shapeof the resilient conductor designated 35. This resilient conductor 35 issimilar to the resilient conductor 12 demonstrated by the secondembodiment shown in FIG. 4 to 6. Moreover, although the terminalelectrode 30 protrudes into the cup-shaped receiving space as shown inFIG. 13 and 14, the resilient conductor 35 protrudes beyond the spacer34 as shown in FIG. 14.

Instead of providing the battery device shown in FIG. 1 to 6, thebatteries 32 with an integral battery device and resilient conductor 31or 35 of the embodiments shown in FIG. 9 to 16 can be provided withinthe flashlights shown in FIG. 7 and 8 for protecting the electrodes frombeing deformed.

While preferred embodiments of the herein invention have been described,numerous modifications, alterations, alternate embodiments, andalternate materials may be contemplated by those skilled in the art andmay be utilized in accomplishing the present invention. It is envisionedthat all such alternate embodiments are considered to be within thescope of the present invention as defined by the appended claims.

What is claimed is:
 1. A battery comprisinga cylindrical casing having arim at either end thereof; a positive terminal at a first end of saidcasing axially inwardly of one of said rims; a negative terminal at asecond end of said casing; a resilient contact in electroconductivecontact with said positive terminal and extending axially outwardly ofthe adjacent said rim.
 2. The battery of claim 1, said negative terminalbeing axially inwardly of the other of said rims.
 3. A batterycomprisinga cylindrical casing having a rim at either end thereof; apositive terminal at a first end of said casing; a negative terminal ata second end of said casing axially inwardly of one of said rims; aresilient contact in electroconductive contact with said negativeterminal and extending axially outwardly of the adjacent said rim.